Locomotive-boiler fire-box.



1. L; NICHOLSON.

LOGGMOTIVE BOILER FIRE BOX.

APPLICATION FILED IIIIEC28|` 1915.

Patente-d June 12, 1917.

zsHEETs-SHEETI.

L. NICHOLSON.

LOCMTIVE BOXLER FIRE BOX.

`APPUCWON man www 191e.

Piltented-fl'u11e 12, 1917.

2 SHEETS-SHEET 2.

mii

UNITED sTATEs PATENT OFFICE.

JOHN L. NIcIIoLs'N, or oHIcAGo, ILLINOIS, Assmnon 'ro AMERICAN ARCH COMPANY,"

0F NEW YORK, N. Y., A CORPORATION OF DELAWARE.

nocoMo'rIvE-BQILER FIRE-Box.

Specification of \Letters,Patentl `:Patented June Application filed December 28, `1915. Serial No. 69,017.

To all whom it may concern:

Beit known that I, J oirN L. NieuoLsoN, a citizen ,ofthe .United States, anda residentof Chicago, county of Cook, and State 'fof Illinois, have lnventedcertain new and useful Improvements in and for Loc'oxnc *tive-,Boiler AFire-Boxes, of which the following is a s cification.

My invention relates to improvements in locomotive boiler lfurnaces, and has speciall reference to limprovements in the refractory arches of such furnaces. The invention is applicable `to refractory arches or batlles lwhich are supported by water-circulating arch tubes and also to those supported from `theside sheets `of thefurnace or Iirebox.

There are two generally approved Ways ofinstalling anal-ch in a locomotive irebox. The lower end ofthe arch is either placed in direct abutment with thelower ypart or throat of the flue sheet, or is spaced away from the flue sheetto provide cinder openings. Such openlngs prevent the accumulationf of cinders on the arch and in the lower flues of theboiler, :but allow relatively .cold air to rpass direct from the ,gratey to the fines. For many y been` in con ict asto whether the lower end ofthe arch should be allowed to abut against fthe liueCsheet, without cinder openings; or

WhetherV the obvious ydetriment of cold air in tlievlower luesis not overbalanced by the ad vantages of` cindergopenings at `the vlower By means of my, invention I'have very simply and effectively solved'the problem by y `providing the cinder openings which all engineers regard asdesirable and at the 7same time overcoming the objections to such cinderl openings. y

My invention ,will be readily understood on reference `,to the drawings that form part oi thisspeciication, in whichz-fFigure l is ,al vertical longitudinalsection of a locomotvewfireboxy embodying my invention z-Fig.

specti've detail of the lower end of the ears railroad engineers have` 2 is a.` horizontalsection thereof substantial1yl ardu-and Fig'. 5 is a sectional detail illusy trating a Inodiied forni of my invention.

The typical locomotive boiler lirebox shown in the dig'aivings comprises the flue, sheet, 2;-the side sheets, 8, 3;--the crown* sheet, 4;-tl1e rear sheet,.5;.-and, the grate,y

(. The other familiar parts shown are, the

boiler shell, 7 forming water legs around f the lirebox; and the lues, 8; and the group of arch tubes, 9, which last extend from the throat sheet, 2', to the upper part of the x rear sheet, 5.

As a first step in my invention, 1 place a mass, 10, of ,refractory material against the throat sheet, 2,,supportingthe saine, preferably by means of a step or bracket, ll., ou the throat sheet, Q', at the forward end of the grate, G. This refractory mass extends from side to side of the irebox and upward tothe level of the lowerinost tlues, As

shown, the mass incloses` the lower parts of the arch tubes. a While the mass may be applied 1n a plastic state and later burned/by the tire on the grate, I prefer, as here shown,

to form it of a nui'nber of separate retrait toryrbrieks shaped to fit the parts, 2', 11, and 9. `Against the upper rear face, l0', of the mass, l0, I place arch struts or spacing bricks, 12. These serve` to space the refractoryrarch, A, rearwardly, 'away from the mass, l0, and the Hue sheet. I uswsuch strutswith arches of all forms, whether the arches are supported upon arclrtubes or upon the sidesheets of `the firebox. When arch tubes are present, the struts, l2, are itted thereto and rest thereon; and are thus e'ectively held against lateral displacemel'it. The arch body, A, shown in the drawings, of the sectional type; that is, composed of a large number of refractory bricks. A", whiclrrest upon the arch tubes. The joints between the several longitudinal rows of arch bricks, A',

,tudinal rows. By this construction I provide a cinder opening, B, at the lower 'end of thearch, A. This opening may be said to extend from sideto side `oi the rebox, although, as shown, it is divided into several parts by the struts o1' bricks, 12.`

. all of the refractory bricks,

` are kept in a state of substantial incandeswith the upper flues.

' vantage I do not sacrifice in the case of my invention,

cence. The presence of the arch, A, causes most of the products of combustion, from the fuel on the grate, to follow the indirect course around the end ofthe arch, but some of the products pass directly to the iues through the cinder openings, B. Obviously, all of the walls of the cinder openings are composed of hot refractory material and the products are therefore raised to a high temperature before reaching the vfines. The refractory mass, 10, is so considerable as to thus insure substantially complete combustion of the Y.

Vwhich escape through the cnder products openin s and the attainment in the lower vflues o temperatures substantially equaling the temperatures of the products which enter the upper flues.

Combustion on the front end of a grate, when covered by an arch is not as active as upon the freer parts of the grate; and much of the air end of the grate is not consumed, nor raised to a high temperature, and, if it were not for the presence of the highly heatedrmass,

10, the products would` enter the lower fiues at temperatures so low as to prevent the expansion and contraction thereof in harmony That is what occurs in the case of the ordinary arch which has cinder openings, and" is the chief cause of leaky lues and damaged. flue sheets. My invention completely overcomes. this difficulty by-insuring temperatures quite as high as can be' attained with an arch that has no cinder openings and yet in securing this adthe advantage of the cinder openings, to wit, the keeping of the arch and lues free. from accumulations of cinders.

rlhe usual '.diiiiculty is accentuated when the irebox 'has a throat sheet that slants rearwardly andbver which the products must pass `to reach the lues. Obviously such a sheet extracts even more heat'from the products than does a vertical throat sheet. By my invention this frequently encountered disadvantage is turned into an advantage, for the slanting throat sheet fur-` nishes a better support for thel refractory mass and a more secure means of attachment bthan can be obtained with a vertical throat sheet; and, furthermcre, the mass arranged upon a slanting throat sheet does not overlap the grate or reduce the grate area.

It will be noted that the top, l0", of the refractorymass, 10, slants, or is rounded, from the Hue sheet towai the grate and does not .present a surface upon which cinders can accumulate; as would be the case if the top of the mass were flat. A further advantage which is drawn through the front of m construction is that theA gases which rise rom the grate toward the cinder opening are not permitted to iow directly to the ues, for the mass, 10, is angled or bowed rearwardly and acts to deflect or bale the gases below and inthe cinder opening, the iame travel, land hence the efficiency of the rebox being considerablyincreased.

My invention is of special utility where the/throat sheet of the firebox is very narrow and the lower parts of the arch tubes are bent upward to provide fuel clearance below the arch at the front end of the grate. Such a case is shown in Fig. 5 in which a narrow throat sheet, 2, and bent arch tubes, 9, serve to support the'refractory mass, 10, fully as well as in the form shown in Figs. 1 to 4. I do not herein claim the clearance increasing construction shown in Fig. 5, having both described and claimed the same in a companion application of even date herewith, Serial No. 69,016.

Having thus described my invention, I

claim as new and desire to secure by Letters ing a main gas passage rearward of the..

arch, the function of said mass being to heat the gases`which pass through said cinder openingr and protect the iues as described. v

2. A locomotive rebox having a slanting throat sheet, in combination with a refrac.h tory,mass` covering and' resting upon and protecting saidl throat sheet and terminating at the lower edge of the flue sheet, and a refractory arch springing'substantially from said mass but separated 'therefrom by a cinder opening, said arch `terminating short of the rear wall of thejfirbox and there being a main gas passage reanward of the arch, the function of said mass being to heat the ases which pass through said cinder openlng and protect the flues as described.

3. A locomotivefirebox, its grate, throat sheet and water circulating tubes, in combination with a refractory mass arranged and water circulating tubes springing there- 1:

from, in combination with a refractory mass ing, said arch termnatin short of the rear uponsaid throat sheet extending both above wall of the rebox and t ere being a. main and below said tubes, and terminating at gas passage rearward of the arch, substan- 10 the lower edge of the Hue sheet, and a retally as and for the purpose described.

A fractory arch supported by said tubes and In testimony` whereof, I have hereunto set springing substantially from said mass, but my hand this 6th da of December 1915. separated from said mass by a cnder open- JO L. NICHOLSON. 

